The present invention generally relates to earth working or tillage implements that have a plurality of earth working tools and that have a mechanism for controlling the draft attributes of an earth working tool independently of other earth working tools of the tillage implement. More particularly, the invention relates to agricultural machinery of the type that has assemblies which perform a plurality of tillage operations during a single pass through the field being tilled and, when desired, planted. The machinery includes an assembly for varying the soil penetration depth of an earth working tool substantially independently of the depth or depths at which other earth working tools of the machine are operated, preferably while also permitting floating and/or tripping of the earth working tool when it engages a subterranean obstacle.
Agricultural machinery for performing tillage operations includes devices that perform multiple operations on the soil during a single pass of the machinery through a field being tilled and/or planted. The types of different operations in this regard include those that break the soil to predetermined depths, which can be subsoil depths, for working the so-called plow pan or compaction layer. Other operations performed by different tool components on this type of machinery include those which are more in the nature of surface soil conditioning and planting functions. Such surface soil conditioning tool components can take the form of devices for cutting through foliage, devices for breaking up earthen clods, devices for directing loosened soil into subsoil grooves, devices for pulverizing the soil and forming same into an acceptable seed bed, as well as devices for depositing seeds and the like into the prepared seed bed. Examples of machinery of this general type are illustrated in Brown et al U.S. Pat. No. 4,055,126 and Harden et al U.S. Pat. No. 4,187,916, the disclosures thereof being incorporated by reference hereinto.
Problems that have been encountered when using this type of machinery are generally caused by the very advantageous features that are provided by this type of machinery, namely the ability to generally simultaneously perform a plurality of earth working functions, and particularly functions that must be carried out at differing soil depths. More particularly, the operation of this type of machinery includes the need to adjust the respective depths at which each of the various components operate. These adjustments are made based upon what the farmer believes to be the soil conditions under which the machinery must operate. Typically, these adjustments are made before the tillage operation is begun or at times when the machinery has been stopped. Adjustment operations typically require the use of hand tools in order to modify the location at which mounting members secure individual earth working components to the tool bar or the like of the tillage implement or machinery. Because such adjustment operations are time-consuming and inconvenient, a typical farmer or agricultural worker will make adjustments only when extremely unsatisfactory conditions develop.
As a result, it is often the case that operational efficiency and economic considerations are ignored or are given a low priority. These considerations include fuel conservation as well as other conditions such as penetration beneath the hard soil pan whenever permitted by soil and weather conditions. Accordingly, there is a need for soil working implements of the type discussed herein which have the ability to accomplish independent adjustment of soil working tools, which adjustment can be carried out easily and preferably from a remote location such as from the cab of a tractor or the like. Even more advantageous properties would be provided by a mechanism that would allow adjustment even while the tillage machinery is in operation moving through a field.
In some cases, the needed adjustment is very difficult to accomplish because the adjusting and mounting components are located within the framework of the implement that supports the components of the machinery. Also, most multiple component tillage equipment currently in use is structured in a manner such that the working depth of a deep tillage component cannot be changed without also changing or in some manner affecting the adjustments of other soil working components that have already been made. The task of properly adjusting each component in a single pass/multiple component unit is especially complicated when a deep tillage component is used integrally with soil finishing tools which are relatively shallow working components. While relatively shallow working components typically do not require extensive adjustment when terrain, soil and weather conditions change, conditions such as slope of the land, moisture content of the soil and composition of the soil will affect the ability of the towing or propelling vehicle to pull the tool having a deep operating profile or a high draft requirement through the soil. Efficiency of operation can be enhanced if the depth of penetration of the high draft tool can be easily varied when these soil conditions change. For example, if an uphill incline in terrain is encountered, it will typically be desirable to reduce the depth of soil penetration of the high draft tool in order to generally offset the increased power needed to propel the implement and vehicle up the slope. The need to decrease depth may also occur when a section of unusually compacted or sticky soil is encountered, or when the propelling vehicle passes through a wet area which reduces traction to the point of causing tire slippage when the high draft tool is operating under deep penetration conditions.
By the same token, one of the important objectives of subsoiler implements having a high draft capability is to break up the plow pan or hard soil pan, which is a generally impervious compacted layer of soil that inhibits root penetration through it and into the moist, looser soil therebelow. This plow pan or hard soil layer is generally found between 8 and 14 inches below the soil surface, and thus the desired working depth needed to break up the plow pan may vary between roughly 10 to 16 inches, depending upon the particular depth of the plow pan. Accordingly, even when slope, soil and weather conditions remain substantially constant, it is at times desirable to adjust the working depth of the subsoiler components in order to track plow pan variations.
With a typical multiple component device having subsoiling capabilities, most operators do not often bother to adjust the components depending upon variations in conditions and plow pan depths. Instead, the farmer or agricultural worker typically adjusts the unit at the beginning of a run based upon the conditions present at the location of the run or that are anticipated will be encountered during the run. Often, this adjustment requires an approximation of the average type of conditions which will be encountered during the run, based upon the experience of the farmer. This estimate of average conditions usually involves selecting a compromise between the desired depth of tool penetration and the power needed to propel the machinery under anticipated conditions of soil, slope and moisture. This type of compromise can result in a situation in which the plow pan is not adequately dealt with at some stages of the earth working operation while excessive power is used at other stages.
These types of problems are avoided by the present invention, which includes a tillage implement having an independent depth control mechanism for controlling the working depth of one of a plurality of soil working components independently of the working depth to which at least one other soil working component is set or adjusted. The controlling mechanism varies the depth of a soil working tool having a high draft requirement, and its operation does not affect the working depth of other earth working components. It is accordingly possible to adjust the working depth of the deep tillage component without significantly modifying or disrupting the surface soil profile that is formed by the tillage implement. In addition, the working depth controlling mechanism is arranged so as to be combined with a mechanism for permitting its soil working tool to float and/or trip when it engages an obstacle.
It is accordingly a general object of the present invention to provide an improved tillage implement having an independent depth control mechanism.
Another object of this invention is to provide an improved tillage implement which permits the farmer or agricultural worker to adjust the working depth of high draft components without significantly affecting the seed bed profile or surface soil profile that is formed by the implement.
Another object of this invention is an improved tillage implement which includes depth control capabilities that can be carried out while the implement is being operated to till a field.
Another object of the present invention is to provide an improved tillage implement which has means to quickly set the desired maximum working depth of a deep tillage component without the time-consuming task of readjusting all of the components in a multi-component tillage tool.
Another object of this invention is to provide an improved tillage implement which achieves enhanced efficiency of operation and fuel conservation, while also maximizing penetration of the hard, impervious plow pan layer that is present in many fields, especially those that have been worked with machinery for a number of years.
Another object of the present invention is to provide a tillage implement that has a deep tillage component which can float or trip over subterranean obstacles while allowing for a change in working depth of the deep tillage component.
These and other objects, features and advantages of the present invention will be clearly understood through a consideration of the following detailed description.